This invention relates to an electronic sewing machine in general, and more particularly to a mechanism and arrangement of a pattern selection system of an electronic sewing machine.
In an electronic or computer sewing machine each stitch pattern is stored in the form of an electronic information specific thereto, in an electronic memory element, and may be read out by selecting and operating a corresponding key arranged adjacent each of the patterns diagrammatically represented on a front panel of a sewing machine housing, to thereby produce the pattern on a fabric material solely or in combination with other pattern or patterns. Meanwhile, recent developments in semiconductor technology have made it possible to considerably increase the capacity of the electronic memory element with the memory element remaining small and resulting in an increase in the number of keys in accordance with the representations of so many stitch patterns stored in the memory element and indicated in the limited space of the front panel of the sewing machine housing. Therefore, the panel is crowded with the keys and the pattern representations.
Thus, as generally known in the prior art, various stitch patterns stored in the electronic sewing machine are classified into two groups depending upon their frequency of use. More particularly, patterns of comparatively high frequency of use have their representations indicated on the front panel and may be directly selected in reference to their representations whereas the other patterns of less frequency of use have the diagramatic representations and the respective pattern numbers each indicated on the underside of a top cover plate of the sewing machine so that the patterns may be selected by operating ten-key switches arranged on the front panel to designate their specific pattern numbers. The operator may know a pattern and the pattern number specific thereto in reference to the list as indicated on the underside of the top cover plate hinged on the machine housing.
In the prior art, character or letter patterns such as alphabet characters and symbols such as period (.), hyphen (-) and question mark (?) are included in the second group of patterns because of their lesser frequency of use and therefore selected indirectly by operation of the ten-key switches to designate the corresponding pattern number. However, actually there may often arise the necessity of continuously stitching in series a plurality of character patterns and/or symbol patterns so as to produce a word or sentence. Such kind of combination stitch can, of course, be produced in the prior art manner. It has however been found troublesome and time-consuming that the ten-key switches are so operated as to select a series of the patterns in reference to the pattern representations and pattern numbers as indicated on the underside of the top cover plate of the sewing machine. This has often resulted in error of the pattern selection.